Check valve assembly for engine fuel injectors



April 22, 1969 D. E. SHOQK 3,439,876

CHECK VALVE ASSEMBLY FOR ENGINE FUEL INJECTORS Filed June 6, 1966 INVENTOR. DA v10 E. SHOOK BY 71ndru8 Sta/KL United States Patent US. Cl. 239-88 3 Claims ABSTRACT OF THE DISCLOSURE There is disclosed an engine fuel injector check valve assembly wherein separate aligned cylindrical members housing one or more check valves in a continuous axial passage therethrough are confined and held in alignment by a resilient sleeve clamping the same and providing a valve subassembly cartridge.

Reference is made to application Ser. No. 559,509, filed June 22, 1966, now Patent No. 3,368,491, jointly by the present applicant and Robert J. Dunlap, and assigned to a common assignee herewith, for Fuel Injection Pump, and in which the valve assembly of the present invention is illustrated.

This invention relates to a check valve assembly for engine fuel injectors as employed with diesel engines.

Where one or more check valves are employed having separate valve containers with the corresponding valve seats provided by adjacent containers, the separate assembly of each container in the tip nut of an injector has required clearances that have a tendency to result in some misalignment between the containers and thereby between the valve members and their seats, so that the valves have not always operated consistently.

The present invention eliminates the individual clearances for the several containers and confines the containers in a slit substantially cylindrical spring sleeve which secures the adjacent containers in alignment.

The accompanying drawing illustrates the best mode presently contemplated for carrying out the invention.

In the drawing:

FIGURE 1 is an axial section through a portion of a fuel injector showing the tip nut and the valve assembly therein;

FIG. 2 is a perspective view of the valve assembly cartridge; and

FIG. 3 is an enlarged transverse section taken on line 3-3 of FIG. 1.

The assembly illustrated comprises the tip nut 1 normally threaded to the end of the injector housing or body 2 and confining the valve cartridge 3 secured between the orifice tip 4 and the cylinder 5.

The valve cartridge 3 comprises the cylindrical containers 6 and 7, the cylindrical spacer 8 and the longitudinally slotted outer spring sleeve 9 which confines the members 6, 7 and 8 in axial alignment.

Members 6, 7 and 8 are of the same diameter, and each has an axial passage 10 therethrough and which connects the central space 11 in cylinder with the axial passage 12 in orifice tip 4.

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Member '6 has an enlarged bore 13 in the upper end of the passage 10 therein, receiving a coil spring 14 pressing upwardly against a check valve member 15 which bears against the lower end of member 7 to normally close the passage 10 therein.

Similarly member 7 has an enlarged bore 16 in the upper end of the passage 10 therein, receiving a coil spring 17 pressing upwardly against a check valve member 18 which bears against the lower end of spacer 8 to normally close the passage 10 therein.

The sleeve 9 is of spring metal of less diameter than the diameter of members 6, 7 and 8, and has a slit 19 extending longitudinally of one side so that the sleeve may be spread to receive the members 6, 7 and 8 and then allowed to spring back upon the members to clamp them tightly in alignment and without clearances that would otherwise allow for misalignment.

As shown in FIG. 3 the sleeve 9 is tightly clamped upon the spacer 8 and is received in tip nut 1 by a suitable assembly clearance 20 which does not interfere with the alignment of the valve containers.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

I claim:

1. In a device of the class described having an orifice tip therein, a check valve assembly having an axial passage therethrough communicating with a central passage in said orifice tip and comprising a cylindrical member with a valve seat surrounding said passage and facing toward said orifice tip, a second cylindrical member in alignment with said first member between the same and said orifice tip and having the passage therethrough enlarged adjacent said valve seat, a check valve member in said enlarged passage normally engaging said valve seat, a spring in said enlarged passage biasing said valve member against said seat, and a resilient sleeve of normally less inside diameter than the outside diameter of said first and second members and clamping the same in alignment.

2. The construction of claim 1 in which said sleeve means comprises a longitudinally slit spring metal sleeve of normally less diameter than said first and second members and adapted to be spread open for insertion and removal of said members, and otherwise adapted to resiliently clamp said members in alignment.

3. The construction of claim 1 in which a plurality of check valves are provided in series within the same sleeve to constitute a valve cartridge subassembly for insertion into the device.

References Cited UNITED STATES PATENTS 2,014,088 9/1935 Nicolas 239-88 2,602,702 7/1952 Kovach 239-89 2,628,866 2/ 1953 Purchas et al. 239-93 2,860,010 11/1958 Sennstrom et al. 239-600 3,368,491 2/ 1968 Shook et al. 239-88 EVERETT W. KIRBY, Primary Examiner.

US. Cl. X.R. 

